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This report presents the results of X-ray fluorescence (XRF) scanning of sediment cores from International Ocean Discovery Program (IODP) Expedition 401 Site U1385, conducted as part of the Investigating Miocene Mediterranean–Atlantic Gateway Exchange (IMMAGE) Land-2-Sea drilling project. The expedition investigated Atlantic–Mediterranean exchange during the Late Miocene, focusing on the Messinian Salinity Crisis and its impact on climate and oceanography. Site U1385 is located on the Promontório dos Principes de Avis, a promontory extending west from the Portuguese margin in the northeast Atlantic, and recovered sediments from the lowermost Pliocene to the Tortonian. XRF scanning provides semiquantitative elemental data at a 2 cm resolution, revealing cyclic patterns in elemental abundances that reflect lithologies and can be correlated cyclostratigraphically with orbital cycles. These data highlight strong positive correlations among terrigenous elements (Al, Si, Ti, Mn, and Ba) and negative correlations between terrigenous and biogenic (Ca and Sr) elements. These results contribute to understanding the paleoceanographic and paleoenvironmental conditions at Site U1385 during the Upper Miocene and Lower Pliocene, providing insights into sediment provenance, diagenetic processes, and climatic variations.
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This content will become publicly available on January 9, 2027
Data report: X-ray fluorescence scanning of sediment cores, IODP Expedition 401 Site U1609, SW Iberia Atlantic margin (Portugal)
International Ocean Discovery Program Expedition 401 recovered 983 m of sediment from Portugal’s southwest margin in the northeast Atlantic Ocean at Site U1609 (37°22.6259′ N, 9°35.9120′ W; 1659.5 m water depth). This site was designed to recover the distal contourites deposited by the Mediterranean Overflow Water contour current from the late Miocene to the Pleistocene. We report semiquantitative elemental results from X-ray fluorescence scanning of sediment cores from Site U1609 (Holes U1609A and U1609B) scanned at a 4–5 cm resolution from ~202 to 509 m core depth below seafloor, Method A, equivalent to ~4.52 to ~7.8 Ma. Raw element intensities (in counts per second) for Al, Si, Ca, Ti, Mn, Fe, Rb, Sr, Zr, and Ba are presented here and correlated with lithofacies variations. We also identify biogenic-terrestrial input proportions and illustrate downcore cyclicity and correlation patterns between terrigenous components (Al, Si, Ti, Mn, and Ba), as well as their anticorrelations with biogenic (Ca and Sr) inputs. The cyclical variations in elemental ratios may help stratigraphic correlation between Holes U1609A and U1609B, astronomical tuning of the spliced record, and sedimentary interpretations of changes to the Mediterranean–Atlantic gateway and the bottom current circulation along the Atlantic margin of Portugal before, during, and after the Messinian Salinity Crisis.
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- Award ID(s):
- 2412279
- PAR ID:
- 10659111
- Publisher / Repository:
- International Ocean Discovery Program
- Date Published:
- Journal Name:
- Proceedings of the International Ocean Discovery Program Expedition reports
- Volume:
- 401
- Issue:
- 201
- ISSN:
- 2377-3189
- ISBN:
- 978-1-954252-94-3
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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